I can't say there's much bad about this game. I feel is just a game that can grow to be addictive, though some levels or modes can be very challenging to tackle and can also grow to be boring after awhile of playing it.
This game is full fledged fun. It's a challenge at first to dodge falling blocks that may crush you as you are drilling your way to victory, but you begin to get quick in speed and build up fast finger work. Playing out of six playable characters makes the game obsessively fun and gives you more variety to the game.